Spatio‐Temporal Analysis of Freight Patterns in Southern California

Project Number

UCD-18-22

Project Summary

Recent results evidenced a shift in the location of warehouses and distribution facilities away from consumer markets (logistics sprawl) in Southern California. These shifts have a negative impact because freight vehicles have to travel longer to reach their destinations. However, during the last decade, this trend has not continued at the same pace, and it may have even reversed. Two main factors potentially explain this phenomenon: the 2008-2009 economic slowdown, and an increased e-commerce activity. E-commerce impacts are relevant for freight planning because of the changes in vehicle size to distribute smaller shipments at higher frequencies, consumer proximity requirements to improve delivery service, and the redistribution of the freight activity and supply chain configurations.

This research will conduct spatio-temporal analyses of Caltrans Weigh-in-Motion data, and traffic counts from the Performance Measurement System to validate some of these assumptions. There is evidence that during 2005-2015, the short-haul volume has increased by 69%, whereas long-haul 59%. The analyses could identify changes in concentrations of trip origins, which by vehicle type could indicate long-haul versus last-mile distribution patterns. The results will help estimate changes in vehicles miles traveled, and more importantly, identify the geographical areas of the most impacted communities.